Heat 2 tablespoons of olive oil in a saucepan over medium heat. Sauté one diced medium onion until translucent, about 5 minutes. Add crushed tomatoes, minced garlic, basil, oregano, parsley, salt, and pepper. Simmer on low heat for 20 minutes.

Cook 12 lasagna noodles according to package instructions until al dente, about 8-10 minutes. Drain and rinse under cold water. Spread on a towel or parchment paper to cool.

In a bowl, mix thawed spinach, ricotta cheese, shredded mozzarella, grated Parmesan, and one egg until well blended.

Preheat oven to 375°F (190°C). Spread about ¼ cup of filling on each noodle. Roll tightly and place seam-side down in a greased baking dish.

Cover roll-ups with remaining sauce, top with mozzarella cheese, and bake for 25 minutes until bubbly.

Let cool for 5 minutes before serving.